Development of Electrode Feed Mechanism for Electrical Discharge Curved Hole Machining Using Slider Crank Chains.

This study deals with developing a new method of machining curved holes with a variety of curvature. Mechanical engineers have taken it for granted that drilling is to machine a straight hole. Therefore, straight holes have been used even in unsuitable cases, for example, pipe lines used in pneumatic or hydraulic equipments and water channels built in molds. They cannot be machined in arbitrary shape and arrangement. This prevents the equipments from being minimized and deteriorates the productivity of molding. To solve these problems, it is strongly required that the curved hole machining method. Hence, to machine curved holes, we have developed a new device consisting of a helical compression spring, wires, and pulleys. However, the curvature of curved holes by the device was limited to a certain one. To overcome the functional problem, slider crank chains are introduced in the device. From experimental results, it is found that the improved device can machine curved holes with a various curvature.